Multi-function printers have the capability of printing on several different types of record media in accordance with the requirements of a user's business. For example, in a retail business, a need may exist in connection with each transaction for making a record on a journal tape and also printing a customer receipt and a multi-part slip, such as may be used in connection with credit card transactions. Printing on these different types of record media in a multi-function printer is typically carried out by a dot matrix printhead which is mounted in the printer for reciprocating traversing movement across the different record media for serial printing of the requied data. During such traversing movement of the printhead, it is important that the various record media being printed upon are constrained in their positions so that they will not bow or otherwise extend outwardly into the path of the printhead, which would cause interference in printer operation and possible damage to the record media. Some mechanism is therefore desirable which is capable of maintaining the record media in the printer in a position in which said media will not interfere with movement of the printhead during printing.